The purpose of this project is to use longitudinal Minimum Dataset (MDS 3.0) resident assessment data to determine the influence of older adults' mental health disorders, especially their depressive disorders and clinically significant depression, on the types and outcomes of pain treatment they receive as residents in VA Community Living Centers (VA CLCs). Effective pain treatment is a key objective throughout the VA health care system, but particularly in VA CLCs. CLC residents are a vulnerable population whose health and functioning characteristics limit their ability to successfully initiate and sustain efforts to obtain effective treatment for heir pain. There is suggestive evidence that mental health disorders, including depressive disorders and clinically significant depression, further impede VA CLC residents' access to effective pain treatment. However, most of this evidence is anecdotal or has been obtained in cross-sectional studies of younger and mixed-age patient populations. Longitudinal data from the newly upgraded Minimum Dataset resident assessment instrument (MDS 3.0) provide a unique opportunity to advance knowledge about the influence of older adults' mental health disorders on the types and outcomes of pain treatment they receive in VA CLCs. For the first time, the MDS assessment survey includes pain treatment items, and an expanded set of pain items, obtained through resident self-report. VA CLC residents are assessed with MDS 3.0 every 3 months; cross-temporal linking of these resident-level data permit prospective and other longitudinal analyses of relationships among mental health disorders, pain treatment, and pain treatment outcomes among VA CLC residents. We will conduct secondary data analyses of longitudinal MDS data obtained from a cohort of older VA CLC residents with diagnosed musculoskeletal disorders in order to achieve these specific aims: (a) to determine the short- term influence of older adults' mental health disorders, particularly depressive disorders, on the pain treatments, and pain treatment outcomes, they experience as VA CLC residents; (b) determine whether four specific MDS-assessed pain treatment recommendations mediate between having a mental health disorder, particularly depressive disorders, and poorer short- term pain treatment outcomes; and (c) ascertain how older adults' baseline mental health disorders, particularly depressive disorders, affect the subsequent 12-month course of their pain treatment outcomes, and the relationship of these 12-month pain treatment outcome trajectories to residents' 12-month physical, cognitive, and behavioral functioning trajectories.